The Study
A randomized study on the effect of vitamin D₃ supplementation on skeletal muscle morphology and vitamin D receptor concentration in older women.
This study tried to see if taking vitamin D pills made older women’s muscles stronger by measuring muscle pieces before and after. Because it randomly gave some women pills and others fake pills, we can guess the vitamin D might have caused the changes — but we’re not super sure because so few women were in the study.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave older women with low vitamin D a daily pill for 4 months to see if it helped their muscles grow.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 561 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — bigger muscle fibers and more receptors suggest vitamin D may help muscles repair or grow, which could help older women stay mobile.
- 2Women who took vitamin D had 30% more vitamin D receptors in their muscle cells and 10% bigger muscle fibers than those who took a placebo.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The Journal of clinical endocrinology and metabolism
Year
2013
Authors
L. Ceglia, Sathit Niramitmahapanya, Mauricio da Silva Morais, D. Rivas, S. Harris, H. Bischoff-Ferrari, R. Fielding, B. Dawson-Hughes
Related Content
Claims (5)
Having more vitamin D in your body might help you build more muscle and store less fat, directing your body’s energy toward making lean tissue instead.
For older women who have trouble moving and don’t have enough vitamin D, taking a daily vitamin D pill for four months can boost a key protein inside their muscle cells by about 30%, which might mean vitamin D directly helps muscle cells communicate better.
For older women who have trouble moving around and don’t have enough vitamin D, taking a daily vitamin D pill for four months might make their muscle fibers about 10% bigger than if they took a sugar pill — which could mean it helps build muscle.
When older women who have trouble moving around get more vitamin D in their blood, their muscle cells seem to respond by making more vitamin D receptors — and this happens no matter how they got the vitamin D, like from pills or sun exposure.
Taking a daily vitamin D3 pill (4000 IU) for four months can help older adults with low vitamin D levels build stronger muscle fibers by increasing the number of vitamin D receptors inside their muscle cells.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.